Preparations

Load the necessary libraries

library(tidyverse) #for data wrangling

Link to the data transformation cheatsheet

https://github.com/rstudio/cheatsheets/raw/master/data-transformation.pdf

Important data manipulation functions:

Task Function Package
Sorting arrange() dplyr
Adding columns mutate() dplyr
Transformations mutate() dplyr
Re-ordering factor levels factor(,levels=) base
Re-labelling factor(,lab=) base
recode() dplyr
Re-naming columns rename(,replace=) dplyr
Filtering/Subsetting indexing base
~ columns select(,...) dplyr
pull(,...) dplyr
~ rows filter(,...) dplyr
Unique combinations distinct() dplyr
Reshaping data pivot_longer(), pivot_wider() tidyr
Split/combine columns separate(), unite() tidyr
Aggregating group_by() summarise() dplyr
group_by() count() dplyr
Merging/joining *_join() dplyr
Extracting data structure expand() tidyr
crossing() tidyr

Piping

Data files

load(file='../data/manipulationDatasets.RData')
dat.1 %>% head

Sorting data

head(dat.1)
#OR
dat.1 %>% head()
#OR
dat.1 %>% head

Adding columns - mutate

Summarising (aggregating) data

Grouping (=aggregating)

Filtering

Reshaping data

Pivot longer

Pivot wider

Combining data

Applied examples